Number Ten by Sue Townsend

A tale of two households: imagine it now. The Browns prepare themselves for bed, the dourly handsome Chancellor giving his glass eye a polish as he prowls up and down in his jim-jams and asks, in a manly Scottish burr, "Read me that bit again will you my dear?" Mrs B clears her throat and picks up Sue Townsend's new book: "when the straps on the high heels had been tightened several times, the make-up applied and the wig tousled and teased into a pleasing Monroe-ish mop, the bathroom door opened and the Prime Minister said, 'You can look now.' "

The noise of Lowland laughter filters through the brickwork to where, as Mrs Blair slaps some cosmetic products on her pretty face, her husband picks up the same volume, sweats as he reads, "The Chancellor moved his empty plate on to a teetering pile of fiscal papers and said, 'I think I could do his job quite well.' "

Townsend has put the cat among the Downing Street pigeons. Prime Minister Edward Clare, searching for the middle way, leaves No 10 dressed as a woman, on a week-long quest to see how real people live. He's joined by Jack Sprat, the regular policeman outside No 10. It's a grim tour that will end up in another No 10, on a battered council estate, a house in use as a temporary crack den. While the PM's away his bulky chancellor, Malcolm Black, with his egg-splattered tie, shifts nearer to the seat of power. The disguises are so thin they might be made of gossamer.

As ever with Townsend, her brilliance lies in her simplicity. The numbing misery of life on a boarded-up estate where all hope has gone is caught in a few deft sentences; the crumbling ruins of the NHS by a sharp description of a night in casualty; the trap of poverty by a 19-year-old mother who can't get on a training scheme because she can't afford to pay for nursery care, and so can't get work.

All of which would make for an earnest but depressing read if every paragraph were not lit by Townsend's warmth and wit, the image of the PM in heels, and some surreal storylines. The PM's wife, Adele, gets a bee in her buzzing bonnet about burial of body parts. She wants amputated limbs given a full burial, and then extends the concept to warts. While things goes to hell in a handcart, the issue grips the nation. A mathematician calculates one coffin could accommodate 51,842 warts.

It's a great comic novel, this tale of two Britains, and should be on the bedside tables of Downing Street. But it won't give an easy night's sleep.